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arXiv · 1808.00513

Pauli-principle driven correlations in four-neutron nuclear decays

P. G. Sharov·L. V. Grigorenko·A. Ismailova·M. V. Zhukov
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Abstract

Mechanism of simultaneous non-sequential four-neutron ($4n$) emission (or `true' $4n$-decay) has been considered in phenomenological five-body approach. This approach is analogous to the model of the direct decay to the continuum often applied to $2n$- and $2p$-decays. It is demonstrated that $4n$-decay fragments should have specific energy and angular correlations reflecting strong spatial correlations of `valence' nucleons orbiting in their $4n$-precursors. Due to the Pauli exclusion principle, the valence neutrons are pushed to the symmetry-allowed configurations in the $4n$-precursor structure, which causes a `Pauli focusing' effect. Prospects of the observation of the Pauli focusing have been considered for the $4n$-precursors $^7$H and $^{28}$O. Fingerprints of their nuclear structure or/and decay dynamics are predicted.

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P. G. Sharov, L. V. Grigorenko, A. Ismailova, M. V. Zhukov. 2018-08-01. Pauli-principle driven correlations in four-neutron nuclear decays. https://doi.org/10.1134/s0021364019130046

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